Some of my 6% polyacrylamide gels seem to mysteriously swell while I'm
warming them up: the gel seems to get squeezed upwards, out of the
plates, and the wells get unusably distorted, and the gel ruined.
I don't think I'm warming them too fast; we used to equilibrate them at
75 watts, and this has happened at 60 watts.
We recently started using dehydrated TBE buffer instead of pre-mixed
stuff, and this does smell of some kind of osmotic problem.
I've also been experimenting with the polymerization recipe.
I often pour the gels 1-to-4 days before they are used, and this has
happened both with older 1-day-old gels. I don't think that's the
trouble. I wrap the comb end with Saran wrap and leave a paper towel
moistened with 1X TBE adjacent to the end to retard drying-out.
Must such gels be stored perfectly flat? Sometimes I leave them inclined
upwards at a very shallow angle (<5°).
Could it be thermal warping of the glass plates?
I will send electronic chocolate-chip cookies or even Rice Crispy treats
to anybody who can solve this problem for me (they're totally tasteless,
but nonfattening, and it's the thought that counts, right?).